At least five civilians have been killed and some 43 others sustained injuries after Turkish troops opened artillery and tank fire on the outskirts of the embattled Syrian city of Aleppo.

The Turkish army launched the deadly attack against al-Bab city, located some 40 kilometers northeast of Aleppo, Bizaah town, some three kilometers east of al-Bab, and Saflaniyeh village on Friday, Lebanon’s Arabic-language al-Ahed news website reported.

It added that at least 12 of the wounded were in critical condition.

The Turkish forces are currently supporting the foreign-backed Free Syrian Army (FSA) militants in their advance towards al-Bab and their planned offensive against Aleppo’s industrial area, which is under the control of the Syrian army.

Over the past four years, Aleppo has been divided between government forces in the west and terrorists in the east, making it a frontline battleground. Backed by Russian air cover, the Syrian army launched operations to reunite the divided northwestern city in September.

On August 24, Turkish special forces, tanks and jets backed by warplanes from the US-led coalition launched their first coordinated offensive in Syria. On the same day, Damascus slammed the intervention as a breach of its sovereignty.

Turkey claimed the incursion was meant to engage both Daesh terrorists in the Syrian-Turkish border area and Kurdish fighters, who were themselves fighting Daesh.

Ankara, however, has long been criticized for refusing to seriously fight Takfiri terrorists. The country also stands accused of allowing potential militants to use its territory for travel and shipment of arms into Syria, and buying smuggled oil from terrorists.

In another development, Daesh militants killed Naser Hajjar, the administrative manager of Aleppo University Hospital in a mortar attack on Friday.

Elsewhere in the country, the Takfiris abducted at least 30 Syrian citizens, who were trying to move from Rakban refugee camp, located in the Jordan-Syria border area, to al-Dhamir town near the capital Damascus.

A man receives treatment at a hospital following a Daesh chemical attack in the Sheikh Maqsood neighborhood of Syria’s Aleppo, April 7, 2016. (Photo by RT)

Daesh’s use of chemical weapons

Meanwhile, the Organization for the Prohibition of Chemical Weapons (OPCW) said in a report on Friday that it had probed 20 cases of the use of toxic arms by Daesh terrorists against Syrian people during the past three months.

Ahmet Uzumcu, the director general of the global watchdog, further said that OPCW experts believed that the terror group might have itself manufactured mustard gas used in Syria and Iraq, in an “extremely worrying” development.

He went on to say that they had received cases of “use of chlorine and unidentified agents in Aleppo and in northern parts of Syria,” such as Idlib, adding that a day earlier the Syrian authorities had sent to the watchdog fresh reports of chemical weapons use against civilians.

Daesh has frequently used chemical weapons in both Syria and Iraq, where it is mainly active.

Syria has been gripped by deadly foreign-backed militancy since March 2011. Over the past few months, terrorists have suffered major setbacks as the Syrian army has managed to liberate several areas.